Some missions that needed to be very dependable in the event of a loss of satellite or other nav capabilities used star nav, even during the day. The cumulative errors can range from a few miles to hundreds of meters or even less on these tactical nav systems. Modern INS capabilities and other methods have become more accurate over time, and have been the dominant approach for some time. There are still some celestial nav systems supported in service.

It reached the amateur market as equipment became low cost and available. If there is a relatively clear view of the sky (free of dense clouds or excessive aerosols), one can acquire position automatigically without any manual alignment or calculations.

My backcountry...

The North Star is a little bit low on the horizon to use in much of Polynesia. However, I was involved in the '90s working with some of these guys (see link below). Mostly in Samoa, Marshall Islands, Feredrated States of Micronesia, Palau, Guam, Yap (topless island) and Saipan. Very scary going to sea with little or no navigation instruments.

https://en.m.wikipedia.org/wiki/Polynesian_navigation

We use the north star in artillery also. We use a technique called the Polaris-Kochab Method to establish accurate directional information for the howitzers. By measuring azimuths and angles between Polaris (North Star) and Kochab (lip of the cup in the Little Dipper) you can establish extremely accurate direction. I have fired howitzer rounds 18 kilometers very accurately with this technique.

Very old school and pretty damn cool. GPS and Inertial Navigation Systems on the howitzer firing GPS guided projectiles makes this pretty much obsolete (until we go to war with a sophisticated enemy who can jam our GPS signals).

JB

If you scroll down from the current photo there is some information about the night camera. Also all the photos each couple minutes sense midnight and some pretty cool photos and videos.

http://www.MtAdams.tv

The North Star (Polaris) is used to extrapolate azimuth and latitude to about 20 degrees North latitude. Basically 5/8 of the Northern hemisphere. If we venture further South we have no celestial body with a fixed GP (ground position).

Pictured below is a universal plotting sheet with a Sun line and an advanced Sun line crossing to obtain a running fix. The earlier Sun line is advanced using dead reckoning (knot log and compass). The method is completely autonomous from any man made navaids.

SixTwoLeemer wrote:
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" My neighboor fancies himself as an avid Astronomer.....he told me the other day that every single star/planet, visible in the sky is part of the Milky Way galaxy except for one....I just can't remember which one it is, that isnt

Anyone know?? "
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Maybe this is a trick question based on semantics. At the very center of the milky way galaxy is a massive black hole. From earth it is located in the region of the sky where the constellation Sagittarius can be seen.

http://www.nasa.gov/mission_pages/chand ... riusA.html

" The center of the Milky Way galaxy, with the supermassive black hole Sagittarius A* (Sgr A*), located in the middle, is revealed in these images. As described in our press release, astronomers have used NASA’s Chandra X-ray Observatory to take a major step in understanding why material around Sgr A* is extraordinarily faint in X-rays. "

It has been purported that the laws of time, space, physics, etc. do not necessarily all apply inside such a structure. Maybe that's what your friend was saying. I'd be curious to know the answer.

Of course a six year old asked me once what donut does not have a hole? I had no clue. She said a " jelly donut". Checkmate

NOTE: Sorry about not using the HTML markups. It seems my computer was not able to use the formatting tools for some reason?

Our human biological eyes have only enough sense to "see" a few stars in the Milky Way. That is what I believe. The other galaxies are too far. . And what we see is no longer there (the latency of light).